Lex,

> Odd, it seemed to work fine in Islands without this change.

Nope it isn't. For example, try

	[:a :b| a+b] valueWithArguments: #(3 4)
	3 perform: #+ withArguments: #(4).

These will fail if the arguments aren't instances of class Array. There are
a few very subtle places which are affected by this change (including
#primitiveDoPrimitiveWithArgs, primitivePerformAt, primititveExecuteMethod
etc).

Cheers,
  - Andreas